Please refer to FIGS. 1A and 1B which show a conventional scanner. The conventional scanner 100 includes a paper positioning bar 101, an import slot 102, a control panel 103, a display device 104, a roller 105 and a scanning unit 106. When a user scans a picture to obtain an electric file via the conventional scanner 100, the paper enters the conventional scanner 100 from the import slot 102 via the roller 105 and then the scanning unit 106 scans the paper to obtain the electric file. The scanning unit 106 could be a Charge-Coupled Device (CCD) or a Contact Image Sensor (CIS), and the paper positioning bar 101 is used to prevent the paper from entering the conventional scanner 100 sideways. Namely, the paper positioning bar 101 keeps the entering track straight.
Please refer to FIG. 2 which shows an image file generated by a conventional scanner. The image file 200 is obtained via a scanning process and includes a picture pattern 201 and a background pattern 202. In order to simply obtain the picture pattern 201, the background pattern 202 must be removed from the image file 200. If a user wants to remove the background pattern 202 by auto-cutting, a software algorithm is always used to recognize and process the background pattern 202. However, in an embedded operating system, the above method not only requires a long processing time due to the low operation speed of the CPU, but also requires a sufficient memory to store the image before cut and the image after cut.
Please refer to FIG. 3 which shows a processed image file. The processed image file 300 is the picture pattern 201 in FIG. 2. The background auto-cutting function is always performed via a software algorithm and the steps of processing are described as follows. The first step is to preset the default background. Then, the second step is to determine an image to be retained. Finally, the third step is to store the retained image. Based on the above reasons, a conventional scanner with the function has the following drawbacks:
(1) A complicated algorithm must be performed to determine the scanning scope or the boundary of the paper.
(2) A big memory must be configured to store the unprocessed image file, which causes the cost increased.
(3) If the object's color level or grey level is too dark, it will be easy for the conventional algorithm to make a mistake so that the image cutting cannot be performed precisely.
Therefore, it would be useful to invent a scanner to circumvent all the above issues. In order to fulfill this need the inventors have proposed an invention “SCANNER.” The summary of the present invention is described as follows.